sanderson



2 Sheets-Sheet 1'.`

.(No Moei.)

R. P. C. SMIDERSOlI,-

COPPER DAM.

Patented June 6, 1882.

mut

zin will N. Penne, Pmwumogmpner, wmngnm n c.

2 sheets-snmJ 2.

(No Model.)

R.P,C.SANDERS0N.

l GOPPERDAM.

Patented J uneV 6"," v'1882.

UNITED 'STATES IPATENT OFFICE.

RICHARD'P. o. sANDEEsoN, 0E NEW YORK, N. Y.

C'oFFERj-DAM.

SPECIFICATION forming part of Letters kPatent No. 259,218, dated June 6, 1882.

Application ined Eebnary 4,1882. (No model.)

To allwhom it may concern Be it known that I, RICHARD PHILIP CHARLES SANDERSON, residing at the city of New York, in the county and State of New York, have invented certain new and useful Improvements in @offer-Dams, ot1 which the following is a specification.

Steamships and other vessels, when their sterns, stern-posts, propellers, or rndders have required repairing or replacing, have commonly been compelled to go to dry-dock, marine railway, or gravin g-dock to have this work done, and this necessitates the removal of all cargo, coal, and ballastto prevent the vessels from being strained, and entails frequent waiting u-ntil there is accommodation for'them, and great expense and loss of time. To avoid these difficulties coffer-dams have been applied to the bows or stems ot vessels; and my invention relates to coft'er-dams of this class.

The object of my invention is to provide a cotl'er-dam which may be applied, withoutloss of time or any previous fitting, to the stem or stern of any vessel within certain limits, and which is so constructed that the space between the walls of the coffer-dam and the sides of the vessel may be more conveniently and effectively closed than in coder-dams heretofore made.

The invention consists in the combination, with a eoier-dam adapted to receive the stem or stern of a vessel, of van upright series -of arms or bars hinged at one end by an upright pivot or 'pivots and adapted to be swung horizontally on their pivot or pivots independently of each other to bring their outer or free ends against the sideV of the vessel. The aforesaid arms or bars may be of such a length that when adjusted against the sides ofthe vessel they will be diagonal or oblique to the length of the vessel, so that the pressure of the water uponthem will press them upon and hold them firmly against the sides of the vessel, and thus more securely close the opening or space between the walls of the eoii'er-dam and the vessel.

The invention also consists in the combination, with a coffer-dam .and the above-described arms or bars, of a rubber, canvas, or other suitable covering placed outside said arms or bars and adapted to be pressed tightly against them by the outside water when the water is' removed from the coder-dam for the purpose of closing all openings and' crevices between and adjacent to the adjustable arms or bars.

The invention also consists in the com-bination, with a coft'er-dam comprising water-tight compartments, of the above-described adjustable arms or bars and valves for allowing .the water in the coder-dam to flow into said Vcompartments, and thereby .lowering the level of water in the coffer-dam so 4rapidly that'the pressure ot' the outside water is quickly made.

available for holding the adjustable arms or bars tightly against the sides of the vessel, and thereby preventing leakage.

In the accompanying drawings, Figurelrepl resents a side elevation of the stern portion of the hull of a vessel and my improved cofferdam applied thereto. Fig.2prepresent'a stern view of one vertical half ot the vessel and a section of half of the co'er-dam 011 the line ac x, Fig. 1. Fig. 3 represents a plan ot one longitudinal half of the Colfer-dam, showing the arms or bars as adjusted to tit the side of a vessel. one side ofthe co'er-dam, upon a larger scale, illustrating asluiceevalve for controlling the ow of water from the inside of the coier-dam to the water-tight compartments; and Fig. 5

Fig. 4 represents a vertical section ot represents a horizontal section of a portion ot' coveringapplied to the outer sides of the adjustable arms or bars and upon the same scale asltiguet.` Y Similar letters of reference designate correspondingparts in all the figures. i

A designates the stern portion of a steamer or other vessel, and B designates theV body of the coft'er-dam, which is preferably constructed ot'plate-iron, strengthened withangle-iron and beams; but it may be made ot' other metal, or of wood, and ot' any desirable or suitable construction. It is here represented as made hollow at the sides and bottom, and such spaces are divided by bulk-heads a into water-tight compartments b. Eachcompartment is connected with the water outside the fcoft'er-dam by a suitably-arranged valve or gate, andwith theeinsideot the coi'er-dam by a sluice-valve, c. (ShownclearlyinFigA.) Each compartment IOO is also connected with the suction-'pipe of thev pumps by suitable pipesand valves, and the pumps are preferably arranged on-a'n attend# antboat, to render the coi'er-damless unwieldy, but might be arranged on the coi'er-dam itself.

All the valves or sluices are provided with lneans for operating them from the top of the coler-dam-as, for instance, the valve c iuFig. 4, which may be operated through coupled rods (l by ahand-wheel or handle on top of the cott'er-dam.

Near the top of the eoft'cr-dam is ahorizontal bulk-head, e, which forms above it an aircompartment, which has sufficient buoyancy to prevent the coier dam from sinking altogether if the attendant should leave the valves for admitting water from the outside into the compartments open too long, or in case ot' any other accident. XVhen the cofter-dam is to be used the valves are opened to admit water from the outside into the compartments, and the coii'er-dam is sunk low enough to permit the vessel to pass into it. The valves are then closed and the Cotter-dam is drawn or pushed under and around the end ot' the vessel into proper position. The water is then pumped ont of the compartments b, and the dam will rise by buoyancy until the keel of the vessel rests iirmly upon the wooden-padded keelson f, as shown in Fig. 2, whereupon the dam is shoved np at the ends and sides, as shown at g, and while all is being made secure and fast all the water is pumped out ot' the compartments.

.At the front end of each side of the cofferdam is an upright series of arms or bars, It, which are all pivoted or hinged by an upright pivot or pintle, h', and are adapted to swing horizontally independently ot' each other. These arms or bars are in close contact with each other, and they are adapted to be swung inward, so that the end of each arm will hear snugly against the part of the skin ot' the vessel opposite to it, and the ends of these arms may be padded, as shown at t' in Figs. 3 and 5, to enable them to have aelose contact with the vessel.

The arms or bars may be swung inward by ropes, chains, or other suitable devices, and

when adjusted snugly against the skin ot' theA vessel they form a wall extending from the keel of the vessel to. above the water-line.

The arms or bars h are here represented as ot'such length that when swung against the vessel they will project outward from the coffer-dam and diagonally or obliquely to the length of the vessel, so that the inward pressure of the water upon their outer sides will hold them securelyagainst the side of the vessel, and thus render them more eective in preventing leakage. When the arms or bars h are all properly brought to bear against the vessel the sluice-valves c, which afford communication between the inside of the cot'erdam and the nowempty compartments b, are all quickly opened, and the water will flow rapidly from the inside of the dam into the compartments until it attains an equal level, the compartments being provided with air-vents to permit the water to liow in. By this means a difference in the height of the water inside and outside the coller-dam is produced, andthe external pressure on the arms 7L will press them all strongly against the Vessel.

To prevent leakage I apply to the outside of the arms or bars 7L a covering, j, of rubber, canvas, tarpaulin, or other suitable material, which, by the external pressure, will be pressed tightly against and into all the crevices between or adjacent to said arms or bars, and will thus render the dam practically watertight. The water is then pumped outfrom the compartments and the vessel is ready for the workmen to begin operations upon it.

The eoveringj may be nailed to the bars or arms 7L in strips; or it may consist of a sheet, as shown in Fig. 5, having one edge, j', fastened to a rope outside and adjacent to the hinges ofthe arms or bars h, and the opposite edge fastened toarope, jz, which may be passed around the vessel.

By my invention I provide for making a coffer-dam which need not be expressly fitted to the vessel to which it is to be applied, but which may be quickly applied to any vessel within certain limits ot' measurement.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination,withaeoi'er-dam adapted to receive the stem or stern of a vessel, of an upright series of arms or bars hinged at one end to the coffer-dam by an upright pivot or pivots, and adapted to be swung horizontally on their pivot or pivots independently of each other to bringtheiropposite ends against the side of the vessel, substantially as specitied.

2. The combination, with the Colfer-dam B, of two series ot arms or bars, h, hinged at their outer ends to the sides ot the cofer-dam, and adapted to swing horizontally independently of each other, the said arms or bars being of such length that when swung inward against the sides of a vessel they will be diagonal or oblique to the length ot' the vessel, substantially as and for the purpose specified.

3. The combination,withacotier-dam adapted to receive the stem or stern of a vessel, of an uprightseries of separately-adjustable arms or bars arranged at each side ot' the coier dam, and adapted to have their ends brought against the sides ot' a vessel, and a covering of canvas, rubber, or other material applied to the outer sides of said arms or bars, substantially as and for the purpose specitied.

4. The combination, with a co'er-dam com prising water-tight compartments and provided at each side with an upright series of separately-adjustable arms or bars, ot' valves for allowing water to ow from the inside of the Colfer-dam into said compartments, substantially as and for the purpose specitied.

RICHARD PHILIP CHARLES SANDERSON.l

Witnesses FREDK. HAYNES, ED. L. MORAN.-

IOO 

